Abstract:
Objective To understand the situation of fine air particle matters (PM2.5) pollution at two communities in Shanghai.
Methods From 2008 to 2009,air samples were collected at fixed sites in two communities (A district was a resident area and B district adjacent the industry area) for monitoring the PM2.5 concentration with membrane gravimetric method every month.Air samples were continuously collected for 7 d each time in order to calculating daily average concentration.Data were analyzed with Wilcoxon rank sum test in SPSS 11.5 software,and adopted median (M) and central quadruplets (P25 to P75) in presence.
Results The monthly PM2.5 level in site B was higher than that in site A,the differences were significant in April and June (P<0.05).The pollution was most serious in winter but least in summer and autumn.The quaternary level of PM2.5 in site B was higher significantly than that in site A in summer (P<0.01).In 2009,the PM2.5 level in site B was higher significantly than that in site A (P<0.001).The concentration values of PM2.5 in two sites were all beyond the Air Quality Planning and Standard of U.S Environmental Protection Agency (U.S.EPA) from 2008 to 2009.The exceeded proportions of PM2.5 concentration in site A were 54.76% and 35.71%,and the maximal exceeding was 4.51 folds.As for the site B,the exceeded proportions were 63.10% and 67.86%,and the maximal exceeding was 5.26 folds.Compared with World Health Organization (WHO) air quality guidelines interim targets Ⅰ,the PM2.5 levels of two communities were exceeded except for site A in 2009.
Conclusion PM2.5 pollution in two communities was serious in winter but less in summer and autumn.The air pollution in site B was more serious than that in site A because of the nearby iron and steel industry.Compared with the air quality standards of U.S.EPA and WHO air quality guidelines interim targets Ⅰ,the PM2.5 levels in two sampling sites were exceeded all.